Fusao Oka is a professor emeritus of Kyoto University and president of the LIQCA Liquefaction Geo Research Institute. Until 1997, he was a professor in the Department of Civil and Earth Resources Engineering of Kyoto University. He specializes in computational geomechanics with particular regard to constitutive equations, consolidation, liquefaction, and strain localization analyses. He organized several international conferences and workshops, such as the Fourth International Workshop on Localization and Bifurcation Theory for Soils and Rocks (1997), the ISSMGE International Symposium on Deformation and Progressive Failure in Geomaterials (1997), the International Symposium on Prediction and Simulation Methods for Geohazard Mitigation (2009), and the 14th International Conference of IACMAG (2014). He has published more than 300 papers on geomechanics and is a co-author of Computational Modeling of Multiphase Geomaterials (CRC Press, 2012). Sayuri Kimoto had been working on geomechanics as an associate professor at Kyoto University for years. She is presently a professor of Osaka Sangyo University. She specializes in the elasto-viscoplastic constitutive equations of soils and the numerical analysis of multiphase geomaterials, such as the behavior analysis of seabed ground due to the production of methane gas. She is a co-author of Computational Modeling of Multiphase Geomaterials (CRC Press, 2012).